1. Field of the Invention
The present invention relates to a figure electing device used in a figure processor, and particularly to a figure electing device for designating a desired figure from among those figures that are displayed on a figure processing image plane in accordance with a pointer.
2. Description of the Related Arts
A conventional figure electing device, as shown in FIG. 14, is composed of coordinates detecting means 1 for receiving position information on an image plane of a point on a figure processing image plane indicated by a pointer and computing the coordinates of that point, figure detecting means 2 for detecting figures located in the vicinity of the computed coordinates and figure determining means 3 for electing a desired figure out of detected nearby figures, and is used by being connected to figure processing equipment 4 for processing figures using the figure processing image plane.
When a pointing device such as a mouse indicates a specific position on a figure processing image plane, a conventional figure electing device receives a position information on the image plane of the indicated point and designates the figure closest to the indicated point. The figure processing equipment 4 performs figure processing such as editing of the figure designated as described above using the figure processing image plane.
The operation of a typical conventional figure electing device will be described in further detail by reference to the flow chart shown in FIG. 15, an example of a display on a figure processing image plane as shown in FIG. 16, and a particularly enlarged diagram thereof shown in FIG. 17 along with FIGS. 18A-18C and FIG. 19.
FIG. 16 illustrates an example of various types of figures which can be objects of figure processing. A user moves a pointer such as an arrow mark, a finger or crossed lines displayed on a figure processing image plane as illustrated in FIGS. 18A through 18C, onto or nearby a figure to be processed by a pointing device such as a mouse, a track ball and so on. When a point is indicated by clicking a button, pushing a key or so on at an appropriate position, the pointing device provides position information in an image plane of the indicated point.
The coordinates detecting means 1 receives the position information in the image plane, and computes and outputs the coordinates of the indicated point (step A1).
The figure detecting means 2 receives the coordinates computed by the coordinates detecting means 1, sets a circle having a fixed radius with the coordinates of the indicated point as the center as shown in FIG. 17 (which shows the vicinity of the indicated point on an enlarged scale), and detects all of the figures included partially or entirely within the circle (step A2). For easy and rapid detection, an improved method is disclosed in JP-A-2-110777, which uses preset rectangules circumscribing the drawn figures, and another method is disclosed in JP-A-2-275574, which uses a table listing figure locations classified based on specific dots to be searched according to a pointed location on the screen. When any figure exists in the vicinity of the indicated point, processing proceeds to step A3, and when no figure exists, the processing routine is ended.
In the step A3, the figure determining means 3 elects the figure located closest to the indicated point out of the nearby figures detected by the figure detecting means 2. Information on the figure thus elected is provided to the figure processing equipment 4, and figure processing such as editing can begin.
However, the above-described conventional figure electing device has the problem that the device sometimes designates a different figure from the one intended by the user because the user may be confused if a pointer having directivity, such as an arrow mark (FIG. 18A). Further, or a finger (FIG. 18B), is used to designate a distant figure in a specific direction if a figure which overlaps other figures as shown in FIG. 19 is designated, the uppermost figure is designated preferentially, and the desired figure cannot be designated.